Crystal structure and superconductivity of YBa₂Cu₃O_7-δ thin films were investigated as functions of oxygen contents and growth temperatures. An effective method for the quantita-tive determination of oxygen content from X-ray diffraction intensity ratio was established through systematic studies on the structural change of the oxygen deficient films. Dependence of cation disorder and T_c on growth temperature, as well as post-annealing temperature has also been obtained. The results suggest an intrinsic relation existing between structure and superconductivity.

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The photoexcited process for NO chemisorbed on Pt surfaces is presented. Desorption and dissociation induced by nanosecond-pulsed visible and ultraviolet laser irradiation have been investigated using angle-resolved photoelectron spectroscopy, reflection-absorption infrared spectroscopy and a resonance-enhanced multiphoton ionization technique. It is found that the photoexcited process shows high reaction selectivity depending on the surface structure and the adsorption site.

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Fundamental principles and recent developments in electron crystallography are explained by way of structure analysis of plant light-harvesting chlorophyll a/b-protein complex associated with photosystem II (LHC-II) . Atomic model of LHC-II had been determined at 3.4Å resolution by electron cryo-microscopy, which included newly developed hardware (an electron cryo-microscope, a cryo-transfer device) as well as specimen preparation techniques.

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A new concept of “the formation of quasi-compounds and their self-ordering on metal surfaces” is reviewed. When Cu (110), Ag (110), Ni (110) are exposed to O₂ at room temperature, one dimensional quasi-compounds of metal-oxygen chains are grown on the surfaces in the [001] direction. The P (n×1) structure of the Ag-O chanins on Ag (110) surface is rationalized by a specific self-ordering of Ag-O quasi-compound on Ag (110) surface. Based on the idea of quasi-compound formation, a new Ag (110) surface on which Cu-O chains are grown in the [110] was prepared. On the other hand, H₂ on Ni (110) surface undergoes the growth of one dimentional Ni-H strings in the [110] direction at room temperature. Coadsorption of H₂ on a p (3×1) Ni-O/Ni (110) surface makes compress the p (3×1) Ni-O to the p (2×1) arrangement. These atom scale phenomena can not be explained by the traditional concept of the adsorption or coadsorption, but can be rationalized by the concept of the quasi-compounds proposed in this review. The concept of the qusi-compounds is inevitable to understand the alloy and/or bimetallic surfaces. For example, prominent catalysis of the Pt-Rh (100) alloy and Pt/Rh (100) and Rh/Pt (100) bimetallic surfaces for the NO_x reduction is explained by the formation of a Rh-O pverlayer on a Pt enriched 2nd layer.

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It has been proposed to maintain strong ligand binding affinity of antibodies, while reducing the immnogenecity of those to human body. Human reshaped antibody is of that kind and has 6 CDRs from mouse and deviates from the human framework structures as small as possible.

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